Parasitiformes

Ixodida

Ixodidae - hard ticks

 

Diagnosis.  Large parasitiform mites (to 6 mm unfed, to 3 cm when engorged) with a prodorsal scutum (covering most of dorsum in males) and with or without one pair of ocelli.  Stigmatal openings on sieve plates behind coxae IV.  Capitulum clearly exposed; denticulate hypostome produced anteriorly; subcapitular groove and tritosternum absent; palps 4-segmented, but appearing to have 3 or fewer segments; chelicerae ending in a pair of slicing digits in a membranous hood.

 

Similar taxa.  Macronyssidae have elongate edentate chelicerae and a well developed tritosternum.  Soft ticks (Argasidae) have papillate integument and the capitulum is mostly hidden by the body.

 

Ecology & Distribution.  Hard ticks are obligate blood-sucking parasites of vertebrates living in nests, in soil, under bark, and on animals.

 

Australian Collections.

Amblyomma, Aponomma, Boophilus, Dermacentor, Haemaphysalis, Hyalomma, Ixodes, Rhipicephalus spp.  Ixodes holocyclus Neumann is not uncommon in litter samples from dry forests and the drier rainforest sites.

References

Johnston DE.  1982.  Acari.  In: Parker, S.P. (ed.)  Synopsis and classification of living organisms.  McGraw-Hill, New York, p. 111.

Krantz GW.  1978.  A Manual of Acarology.  OSU Bookstores: Corvallis.

Roberts FHS.  1970.  Australian Ticks.  CSIRO: Melbourne.

Sonenshine DE.  1991.  The Biology of Ticks.  Oxford University Press: Oxford.